Feed numbers and letters into the machine. Learn to write, read, and find the value of math expressions.
Engage 5 min · Explore 10 min · Explain 8 min · Apply 15 min · Reflect 8 min. Total ≈ 46 min. Distributive property questions may need 5 extra minutes for newcomers.
Engage — think-pair-share (partners). Explore — pairs on shared device. Apply and Reflect — independent. Compare reflections with a partner before submit.
You have 3 boxes. Each box holds the same number of marbles. You do not know how many! We can call that unknown number b.
Think: How can we write "3 boxes of b marbles" using math?
Open the tools below to play and explore expressions.
Play the 3D Expression Engine Unit 6 Math Hub Read the Math NovelTip: In the game, feed blocks into the machine to build expressions like 3 × b.
Read these key words. Then read the worked examples.
| Word | Easy meaning | Example |
|---|---|---|
| Expression | Numbers and letters joined by math signs. No equals sign. | 3b + 5 |
| Variable | A letter that stands for an unknown number. | b |
| Coefficient | The number multiplied by a variable. | In 3b, it is 3 |
| Exponent | Small raised number. It tells how many times to multiply the base by itself. | 5² = 5 × 5 = 25 |
| Evaluate | Put in a number for the letter and find the value. | If b = 4, then 3b = 12 |
| Distributive | Multiply the outside number by each term inside the parentheses. | 2(x + 3) = 2x + 6 |
| Equivalent | Two expressions that always give the same value. | 2(x + 3) and 2x + 6 |
Rule: 3b always means 3 × b. The number in front is the coefficient.
Quick Check — try these first and check yourself:
SC1. What is the value of 3²?
SC2. Evaluate 4x + 1 when x = 3.
SC3. Use the distributive property. Which expression is equivalent to 2(n + 4)?
Type your answer in each box. Then press Check My Work.
| Level | Score | What it looks like |
|---|---|---|
| 4 — Exceeds | 6/6 | All expressions, evaluations, and distributive property correct. Reflections use math vocabulary precisely and explain reasoning. |
| 3 — Meets | 4–5/6 | Correctly writes and evaluates expressions; may make a minor error with exponents or distribution. Reflections are complete. |
| 2 — Approaching | 2–3/6 | Can identify coefficient and variable but struggles to apply exponents or distributive property. Reflections are brief. |
| 1 — Beginning | 0–1/6 | Confuses expressions with equations, or cannot yet evaluate by substitution. Needs re-teaching of core concepts. |
Write 2–4 sentences for each prompt. Use math vocabulary: variable, coefficient, exponent, evaluate, equivalent. Your answers are saved in your PDF/DOC and count toward your grade.
Deliverable: Complete both reflections, press Check My Work above, then submit your PDF or DOC to the class folder.
When you finish, use Save as PDF or Save as DOC at the top to turn in your work.